Non-inflammable acetyl-cellulose composition.



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WTLLIAM G. LINDSAY, OF NEW YORK, N. Y., ASSIGNOR TO THE CELLULOIDCOMPANY, A CORPORATION OF NEW JERSEY.

NON-INFLAMMABLE ACETYL-CELLULOSE COMPOSITION.

t,ll33,35.

Ito Drawing.

To all whom it may concern:

Be it known that l, WILLIAM GonsoN LINDSAY, a citizen of the UnitedStates, re-

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siding at New York city, in the county of New York and State of NewYork, have invented certain new and useful Improvements inNon-Tnfiammable Acetyl-Cellulose Compositions, of which the following isa full, clear, and exact specification.

This invention relates to improvements in non-inflammable photographicfilms, and relates to a non-inflammable transparent composition ofmatter containing an organic graph apparatus. The high inflammability'of nitro-cellulose films has called for a sub' stitute that would beless hazardous in operatingicinematograph and similar apparatus.eretofore, it has been proposed to form films of substances other thannitrocellulose, but such films have presented several objections, sothat for practical'puroses the nitro-cellulose film is still preerred tosuch substitutes. These prior substitutes have a tendency to harden orbecome brittle, and so far as l am aware of none is non-inflammable. Thethin sheet or strip of film made in accordance with my invention is freefrom all danger ofinfilamma bility or ignition, and inaddition-istransparent and possesses permanently a "high degree ofstrength and tenacity.'

lln carrying out my invention I may take any acety l cellulose which issoluble in ace tone to which has been added triphenylphosphate ashereinafter described." The amount of acetone, which has a relativelylow boiling point of 58 C. employed depends upon the consistency desiredfor 1 the solution upon glass 'or other smooth surface. To this solutionI may add suitable quantities of a restraining agent, such as acetylenetetrachlorid, which has a relatively high boiling point of 147 C. orequivalent substance. The film or strip may now be formed by spreadingthe solution upon any smooth surface, such as glass. The solvents arenow allowed to evaporate in the usual way, which results in leaving adried and hardened film or strip. The acetone, or low boiling solvent,evaporates from the film in a comparatively short time, but theevaporation of the acetylene tetrachlorid, or high boiling solvent,proceeds more slowly, and a very long time may elapse before there issubstantially complete evap orationthereof. The film, however, will bedry and hard enough for use in a very considerable time before the highboiling solvent has substantially evaporated.

The product obtained by following the above mentioned steps possessesgreat strength and tenacity, is transparent and is substantiallynon-inflammable. The triphenylphosphate produces a decided strengthening.and non-inflammable efiect.

To render permanent the strengthand te- Specification of Letters Patent.Pat gntgdl Map. 3Q, 19115 Application filed May 5, 1909. Serial No.494,180.

nacity of the product urea in proper proportions may be employed inaddition to the triphenylphosphate.

l[ have found the following ingredients with'the'proportions asindicated to give most excellent results:

Parts by weight.

- Acetyl cellulose; 100 Acetone 300 Triphenylphosphate 15 Acetylenetetrachlorid 4C5 Urea 2 llt will beunderstood that the product formed inaccordance with this invention is not limited to the exact proportionsset forth above, and that my invention is not limited to the specificsubstances as indicated. Any acetyl cellulose which is soluble in amenstruum in the presence oftriphenylphosphate, or equivalent substanceis suitable. The acetone ingredient may be replaced in part or in wholeby any suitable solvent. The acetylene tetrachlorid may be replacedentirely or in part by equivalent substances. The degree of thinness ofthe willcontrol to some extent the extreme proportions of the substancesused to obtain my product. A 10-part proportion of triphenylphosphategives a satisfactory strength and produces a substantiallynoninflammable product; in extremely thin films it might be founddesirable to raise the proportion, say to 25 parts. A very smallproportion of urea will prevent or retard the tendency to becomebrittle, so that for many purposes the proportion need not be two percent.

The invention set forth in this application is of special utility as afilm or plate for photographic purposes, both as negatives and aspositives, and particularly in the. form of long strips for use incinematograph and similar apparatus. The film made in accordance withthis invention is highly flexible and possesses unusual strength, andwill not burn with a self-sustaining flame even when the film hangspendant. It is to be noted that the qualities of strength and pliabilityof my product are permanent in character, and are capable of receivingand retaining sensitized emulsion for use in photographic processes.

Having thus described my invention, I declare that what I claim as newand desire to secure by Letters Patent, is

1. A product comprising an organic esterified compound of cellulose andtriphenylphosphate obtained by dissolving the same in a solvent commonto both, and then permitting the solution to dry and harden byevaporation.

2. A product comprising an organic acid ester of cellulose andtriphenylphosphate obtained by dissolving the same in a solvent commonto both, and then permitting the solution to dry and harden byevaporation.

3. A product comprising an organic es- .terified compound of celluloseand a noninflammable material, which is insoluble in water, obtained bydissolving the same in a solvent common to both and a fluid restrainingagent, and then permitting the solution to dry and harden byevaporation.

4. A product comprising an organic esterified compound of cellulose andtriphenylphosphate obtained by dissolving the same in a solvent commonto both, to which solvent has been added a fluid restraining agent andthen permitting the solution to dry and harden by evaporation.

5. A product comprising an acetyl cellulose and triphenylphosphateobtained by dissolving the same in a mixture of acetone and acetylenetetrachlorid, and then permitting the solution to dry and harden byevaporation.

6. A product comprising an acetyl cellulose and triphenylphosphateobtained from dissolving the same in a solvent common to both, to whichhas been added a fluid restraining agent, and then permitting the sameto dry and harden by evaporation.

7. A product comprising acetyl cellulose and triphenylphosphate obtainedby dissolving the same in acetone, and then permitting the solution todry and harden by evaporation.

8. A product comprising acetyl cellulose, triphenylphosphate and ureaobtained by dissolving the same in a solvent of the acetyl cellulose andtriphenylphosphate to which has been added a fluid restraining agent,and then permitting the solution to dry and harden by evaporation.

9. A product comprising acetyl cellulose,

triphenylphosphate and urea obtained byv dissolving the same in amixture of acetone and acetylene tetrachlorid, and permitting thesolution to dry andharden by evaporation.

In testimony whereof I aflix my signature in presence of two witnesses.

WILLIAM G. LINDSAY. Witnesses:

HENRY J. LUCKE, GEo. N. KERR.

